Idaho teenager planned attack on churches in support of ISIS, says FBI

Alexander Scott Mercurio accused of attempting to provide material support or resources to a 'designated foreign terrorist organisation'

An ISIS member waves the extremist group's flag in Raqqa, Syria. Reuters

An Idaho teenager has been arrested by the FBI under suspicion of attempting to carry out mass shootings at churches in support of ISIS.

Alexander Scott Mercurio, 18, was accused in a court filing of “attempting to provide material support or resources to a designated foreign terrorist organisation”.

He contacted ISIS affiliates and expressed support for the organisation and other extremist groups, according to the FBI, which cited "confidential human sources".

Mr Mercurio is also accused of spreading ISIS propaganda online.

“At the beginning of 2024, his conduct escalated to Mercurio planning to carry out a suicide attack on a church(es) in Coeur d'Alene, Idaho,” said the filing, released on Tuesday.

“His attack plan involved using flame-covered weapons, explosives, knives, a machete, a pipe and ultimately firearms.”

The FBI said it first became aware of Mr Mercurio's activities in 2021, when it was investigating a fund-raising network that uses cryptocurrency exchanges and other financial services platforms to support ISIS and other organisations operating in Syria.

It said that after Mr Mercurio was identified, an investigation of his computer revealed documents and photos showing his support for ISIS, including an image in which he appeared in front of the group's flag.

“I am going to perform a martyrdom operation very soon,” he allegedly wrote in one message. “The targets will be the various churches in my town,” he said, as he wanted to “fix” the problem of too many such places of worship in the area.

He added that he would carry out his plan in the last days of Ramadan, according to the court filing.

Mr Mercurio was arrested by the FBI's Joint Terrorism Task Force the day before his alleged planned attack.

The FBI executed a search warrant at Mr Mercurio's family's home, CBS reported, with investigators seizing a metal pipe, butane, hand sanitiser, a machete and several firearms locked in his father's wardrobe.

A court date for the case has yet to be set.